SDL exists for Ubuntu Touch. Also, pygame and pygame-sdl (both only python2 unfortunately)
However, you have to enlarge your system.img partition in order to have room for it (Atleast on Nexus 5) See: https://github.com/plasma-mobile/plasma-phone-dev-setup/blob/master/usr/bin/resize-root-partition
Then sudo remount / -o rw,remount && sudo apt-get update && sudo apt-get install python-pygame etc
I've been trying to create a click package with some pygame testing code, but not managed to get the dependency setting in clickable.json to install python-pygame-sdl2..

Interesting. Sad that the performance was that bad.
Have you had a look at https://github.com/renpy/pygame_sdl2?
(It has a pygame compatible mode)
There is at least one game for Sailfish that uses that pygame_sdl2.